Solvent-free heating viscosity-reducing glue as well as preparation method and use method thereof

Abstract

The invention provides solvent-free heating viscosity-reducing glue as well as a preparation method and a use method thereof, and the solvent-free heating viscosity-reducing glue is prepared from the following raw materials in specific parts: acrylate resin, an acrylate structural monomer, an acrylate functional monomer and an acrylate reaction monomer, according to the solvent-free heating viscosity-reducing glue, an acrylate structural monomer, an acrylate functional monomer and an acrylate reaction monomer are selected and matched, and the molecular weight regulator is added, so that the obtained solvent-free heating viscosity-reducing glue has relatively high bonding strength with a base material after being subjected to UV curing; in addition, viscosity reduction can be carried out in a heating mode, no adhesive residue exists after viscosity reduction, and meanwhile the beneficial effects of being small in smell, high in light transmittance and not needed to be stored in a dark place are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of glue, and in particular relates to a solvent-free heating viscosity-reducing glue and a preparation method and a use method thereof. Background Art

[0002] With the upgrading of the electronics industry, the demand for anti-sticking protective film in many fields such as wafer cutting, semiconductor chips, OCA bonding and positioning has been increasing. The anti-sticking tape should have the purpose of stable positioning in the initial stage, and play a protective role in the cutting or etching process. It should be easy to remove without leaving any residue during the later dismantling. This requires the tape to maintain a high adhesion in the initial stage and quickly reduce the adhesion after UV irradiation.

[0003] At present, there are two main types of anti-sticking tapes: UV anti-sticking and foaming anti-sticking. Among them, the foaming anti-sticking mainly relies on the foaming particles in the glue to expand and reduce the bonding area of ​​the glue to reduce the sticking. There is a lot of residual glue after bonding and the foaming particles cause the glue to have a low transmittance. UV anti-sticking adhesive has super high adhesion, which can ensure that the object being glued remains stable during the processing process. After the processing is completed, its adhesion can be instantly reduced by ultraviolet radiation. It can be easily removed from the bonded material without affecting the performance of the processed object. It is widely used in the cutting and etching of semiconductor wafers and other processes. CN114058289A discloses a UV anti-sticking adhesive and a UV anti-sticking tape. In order to solve the problem that the peeling strength of the adhesive film formed by the existing UV adhesive is high after UV irradiation, the UV adhesive comprises the following components: 30 to 50 parts of acrylate resin, 5 to 10 parts of cationic curing resin, 7 to 14 parts of multifunctional monomer, 0.1 to 1 part of free radical photoinitiator, 0.1 to 1 part of cationic photoinitiator, and 2 to 4 parts of crosslinking agent, wherein the parts are parts by mass. The adhesive film formed by the UV adhesive has high peeling strength before UV irradiation and low peeling strength after UV light irradiation, can adhere to the protected material without falling off, has low adhesion after UV light irradiation, is easy to be peeled off from the protected material, and is not easy to leave residual adhesive.

[0004] However, most of the UV viscosity-reducing adhesives provided in the prior art, including the above-mentioned invention, are prepared by adding multifunctional monomers and photoinitiators to acrylic pressure-sensitive adhesives. In the initial stage, the acrylic pressure-sensitive adhesive provides high peeling force. After use, the multifunctional monomers in the pressure-sensitive adhesive are cured by the initiator through ultraviolet light irradiation, causing the pressure-sensitive adhesive molecules to lose their wetting fluidity. At this time, the pressure-sensitive adhesive loses its viscosity and becomes less viscous. However, since the UV viscosity-reducing adhesive contains multifunctional monomers and initiators, it is greatly affected by the environment. The light and high temperature during transportation and storage will cause the performance of the UV viscosity-reducing adhesive to change, and even deteriorate and lose its initial viscosity.

[0005] Therefore, in order to solve the above technical problems, it is urgent to develop a solvent-free heating viscosity-reducing glue which has strong adhesion after UV curing and can be heated to reduce viscosity. Summary of the invention

[0006] In view of the deficiencies in the prior art, the object of the present invention is to provide a solvent-free heating deviscous glue and a preparation method and a use method thereof. The solvent-free heating deviscous glue has good adhesion to the substrate after UV curing, and can be deviscous by heating after bonding. There is no residual glue after deviscousing. At the same time, it also has the advantages of low odor, high light transmittance and no need to be stored away from light.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a solvent-free heating viscosity-reducing glue.

[0009] The solvent-free heating viscosity-reducing glue comprises the following components in parts by weight:

[0010]

[0011]

[0012] The raw materials for preparing the solvent-free heating viscosity-reducing glue provided by the present invention include acrylate resins, acrylate structural monomers, acrylate functional monomers, acrylate reaction monomers, photoinitiators, molecular weight regulators, isocyanates and sealing agents; the adhesive film formed by the solvent-free heating viscosity-reducing glue after UV curing has high adhesion to the substrate and high cohesive strength, and can be de-viscous by heating after bonding with the substrate, because the hydroxy acrylate in the acrylate reaction monomer can be cross-linked with the curing agent after heating, so that the cohesion of the adhesive layer is further improved, resulting in the loss of wetting fluidity of the glue, and the pressure sensitivity is greatly reduced and can be easily separated, so there is no residual glue after the viscosity reduction, and at the same time, because no plasticizer and tackifier are added to the raw materials for preparing the solvent-free heating viscosity-reducing glue, the glue has the advantages of small odor, high light transmittance and no need to be stored in the dark.

[0013] The acrylic resin may be present in an amount of 20 parts by weight, 30 parts by weight, 40 parts by weight, 50 parts by weight, 60 parts by weight, 70 parts by weight, or 80 parts by weight.

[0014] The acrylic acid ester structural monomer may be 20 parts by weight, 30 parts by weight, 40 parts by weight, 50 parts by weight, 60 parts by weight or 70 parts by weight.

[0015] The acrylate functional monomer may be 5 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight or 15 parts by weight.

[0016] The acrylic acid ester reactive monomer may be 3.2 parts by weight, 3.4 parts by weight, 3.6 parts by weight, 3.8 parts by weight, 4 parts by weight, 4.2 parts by weight, 4.4 parts by weight, 4.6 parts by weight or 4.8 parts by weight.

[0017] The photoinitiator may be 2 parts by weight, 3 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, etc.

[0018] The isocyanate may be 4 parts by weight, 4.5 parts by weight, 5 parts by weight, 6 parts by weight, 7 parts by weight, etc.

[0019] The molecular weight regulator may be 0.1 parts by weight, 0.2 parts by weight, 0.3 parts by weight, 0.4 parts by weight, or 0.5 parts by weight.

[0020] The sealing agent can be 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight or 5 parts by weight, etc.

[0021] Preferably, the acrylic resin includes polyurethane acrylate and / or aliphatic polyester acrylate, more preferably polyurethane acrylate, and even more preferably polyurethane acrylate having a glass transition temperature not higher than -10°C (e.g., -12°C, -14°C, -16°C, -18°C or -20°C, etc.).

[0022] Preferably, the acrylic ester structural monomer is a monofunctional acrylic ester structural monomer.

[0023] Preferably, the glass transition temperature of the monofunctional acrylate structural monomer is not higher than 0°C, for example -10°C, -20°C, -30°C, -35°C, -40°C, -45°C or -50°C.

[0024] Preferably, the monofunctional acrylic ester structural monomer includes any one of isodecyl methacrylate, isodecyl acrylate, isooctyl acrylate, isooctyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, isononyl methacrylate, isononyl acrylate, tridecyl methacrylate, tridecyl acrylate, heptadecyl methacrylate, heptadecyl acrylate, octadecyl methacrylate, octadecyl acrylate, eicosyl methacrylate, eicosyl acrylate, isooctadecyl methacrylate, isooctadecyl acrylate, lauryl acrylate, tetrahydrofuran acrylate or ethoxyethoxyethyl acrylate, or a combination of at least two thereof.

[0025] Preferably, the acrylate functional monomer is an acrylate monomer containing a carboxyl group and / or an amide group.

[0026] Preferably, the acrylate functional monomer includes any one or a combination of at least two of acryloylmorpholine, dimethylacrylamide, diethylacrylamide or carboxyethyl acrylate.

[0027] Preferably, the acrylic acid ester reactive monomers include hydroxy acrylic acid esters.

[0028] Preferably, the acrylic acid ester reactive monomer includes any one of hydroxyethyl acrylate, hydroxypropyl acrylate or hydroxybutyl acrylate, or a combination of at least two thereof.

[0029] Preferably, the photoinitiator includes any one of 1-hydroxycyclohexyl phenyl ketone, ethyl 2,4,6-trimethylbenzoylphenylphosphonate or 2-hydroxy-2-methyl-1-phenyl-1-propanone, or a combination of at least two thereof.

[0030] Preferably, the molecular weight regulator comprises a thiol molecular weight regulator.

[0031] Preferably, the isocyanate includes isocyanate having a functionality of not less than 3 (eg, 3, 4, 5 or 6, etc.).

[0032] Preferably, the polyisocyanate includes any one or a combination of at least two of toluene diisocyanate trimer, toluene diisocyanate trimer biuret, hydrogenated toluene diisocyanate trimer, hydrogenated toluene diisocyanate biuret, diphenylmethane diisocyanate trimer, diphenylmethane diisocyanate biuret, hydrogenated diphenylmethane diisocyanate trimer, hydrogenated diphenylmethane diisocyanate biuret, hexamethylene diisocyanate trimer, hexamethylene diisocyanate biuret, isophorone diisocyanate trimer or isophorone diisocyanate biuret, and more preferably hexamethylene diisocyanate trimer and / or hexamethylene diisocyanate biuret.

[0033] Preferably, the blocking agent includes any one of small molecule alcohol, phenol, ketoxime or small molecule amine, or a combination of at least two thereof.

[0034] In a second aspect, the present invention provides a method for preparing the solvent-free heating viscosity-reducing glue as described in the first aspect, the preparation method comprising: mixing acrylate structural monomers, acrylate functional monomers and acrylate reaction monomers under light-proof conditions, adding isocyanate to react, then adding a blocking agent to block, and then adding a photoinitiator, an acrylate resin and a molecular weight regulator to mix to obtain the solvent-free heating viscosity-reducing glue.

[0035] Preferably, the preparation method specifically comprises: mixing acrylate structural monomers, acrylate functional monomers and acrylate reaction monomers under light-proof conditions, adding isocyanate and reacting at 60-80°C (for example, 62°C, 64°C, 66°C, 68°C, 70°C, 72°C, 74°C, 76°C or 78°C, etc.) for 60-120min (for example, 70min, 80min, 90min, 100min or 110min, etc.), then adding a capping agent and continuing the capping reaction at 60-80°C for 30-60min (for example, 35min, 40min, 45min, 50min or 55min, etc.), continuing to add a photoinitiator, an acrylate resin and a molecular weight regulator for mixing, and cooling to room temperature to obtain the solvent-free heating viscosity-reducing glue.

[0036] In a third aspect, the present invention provides a method for using the solvent-free heating viscosity-reducing glue as described in the first aspect, the method comprising the following steps:

[0037] (1) coating the solvent-free heating and viscosity-reducing glue on the substrate or release film to be bonded, and light curing to complete the bonding of the solvent-free heating and viscosity-reducing glue;

[0038] (2) Heat-treating the solidified solvent-free heating viscosity-reducing glue obtained in step (1) to complete the stripping of the solvent-free heating viscosity-reducing glue.

[0039] The solvent-free heated viscosity-reducing glue provided by the present invention can be directly coated on the surface of the substrate to be bonded when in use, and photocured to make the solvent-free heated viscosity-reducing glue and the substrate bonded together, or the solvent-free heated viscosity-reducing glue can be pre-coated on a release film, and photocured to form a tape similar to a pressure-sensitive adhesive, and when in use, the release film is peeled off and then attached to the surface of the substrate to be bonded. When it is necessary to peel the solvent-free heated viscosity-reducing glue from the substrate, the attached substrate can be directly heat-treated so that the peeling force between the glue and the substrate is greatly reduced until most of the peeling force disappears, and the glue can be easily peeled from the substrate.

[0040] Preferably, the energy of the light curing in step (1) is 300 to 1000 mJ / cm 2 , for example 400mJ / cm 2 、500mJ / cm 2 、600mJ / cm 2 、700mJ / cm 2 、800mJ / cm 2 or 900mJ / cm 2 wait.

[0041] Preferably, the heating temperature in step (2) is 130-150°C, for example, 132°C, 134°C, 136°C, 138°C, 140°C, 142°C, 144°C, 146°C or 148°C.

[0042] Preferably, the heating time in step (2) is 10 to 20 minutes, for example, 12 minutes, 14 minutes, 16 minutes, 18 minutes or 20 minutes.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] The raw materials for preparing the solvent-free heating viscosity-reducing glue provided by the present invention include acrylate resin, acrylate structural monomer, acrylate functional monomer, acrylate reactive monomer, photoinitiator, molecular weight regulator, isocyanate and blocking agent. By selecting acrylate structural monomer, acrylate functional monomer and acrylate reactive monomer for matching, and adding molecular weight regulator, the obtained solvent-free heating viscosity-reducing glue has high bonding strength with the substrate after UV curing, and can be de-vised by heating, and there is no residual glue after the viscosity reduction. At the same time, it also has the advantages of small odor, high light transmittance and no need to be stored in the dark. DETAILED DESCRIPTION

[0045] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0046] The information of some raw materials involved in the specific implementation of the present invention is as follows:

[0047] (1) Polyurethane acrylate resin

[0048] Polyurethane acrylate A: from Changxing Chemical, DR-U367-1, Tg is -44.5℃;

[0049] Polyurethane acrylate B: from Guangzhou Songda Chemical, SD9211, Tg is -33℃;

[0050] (2) Acrylate structural monomers

[0051] Isodecyl acrylate: Tg is -58°C;

[0052] Butyl acrylate: Tg point is -55°C;

[0053] (3) Acrylate functional monomers

[0054] Diethylacrylamide: Tg point 81°C;

[0055] Carboxyethyl acrylate: Tg is 37°C;

[0056] (4) Acrylic acid reactive monomer

[0057] Hydroxybutyl acrylate: Tg is -60°C;

[0058] (5) Photoinitiator

[0059] 1-Hydroxycyclohexylphenyl ketone: photoinitiator 184;

[0060] Ethyl 2,4,6-trimethylbenzoylphenylphosphonate: photoinitiator TPO;

[0061] (6) Molecular weight regulator: dodecyl mercaptan;

[0062] (7) Isocyanate

[0063] HDI trimer: Wanhua Chemical, HT-100;

[0064] HDI biuret: Wanhua Chemical, HB-100.

[0065] Isophorone diisocyanate: Wanhua Chemical.

[0066] Examples 1 to 11

[0067] A solvent-free heating viscosity-reducing glue, the components in the raw materials for its preparation are shown in Table 1, and the amount of each component is "parts by weight":

[0068] Table 1

[0069]

[0070] The preparation method of the solvent-free heating viscosity-reducing glue provided in Examples 1 to 11 includes: under light-proof conditions, evenly mixing acrylate structural monomers, acrylate functional monomers and acrylate reaction monomers, adding isocyanate to react at 60°C for 120 minutes, then adding a blocking agent to carry out a blocking reaction at 60°C for 30 minutes, then adding a photoinitiator, an acrylate resin and a molecular weight regulator to mix, and cooling to room temperature to obtain the solvent-free heating viscosity-reducing glue.

[0071] Comparative Examples 1 to 4

[0072] A solvent-free heating viscosity-reducing glue, the components in the raw materials for its preparation are shown in Table 2, and the amount of each component is "parts by weight":

[0073] Table 2

[0074]

[0075] The preparation methods of the solvent-free heating viscosity-reducing glue provided in Comparative Examples 1 to 4 are the same as those in Example 1.

[0076] Performance Test:

[0077] The glue provided in the examples and comparative examples was evenly coated on a PET with a thickness of 50 μm and heated at 750 mJ / cm 2 The release film was attached under energy for curing, and the release film was peeled off to obtain a PET tape with a thickness of 50 μm, and the following tests were performed;

[0078] (1) Peel strength: The prepared PET tape was attached to a clean glass and the 180° peel strength was tested under the following conditions: temperature of 23°C, peel speed of 300 mm / min, and relative humidity of 50%;

[0079] (2) Adhesion reduction: The PET tape attached to clean glass was baked at 135°C for 15 min and then the peeling force was tested.

[0080] The solvent-free heating viscosity-reducing glue provided in Examples 1 to 11 and Comparative Examples 1 to 4 was tested according to the above test method. The test results are shown in Table 3:

[0081] Table 3

[0082] Peel force (N / in) Viscosity reduction (N / in) Example 1 10.24 1.25 Example 2 7.71 1.02 Example 3 8.66 1.78 Example 4 12.55 1.21 Example 5 9.16 1.36 Example 6 10.56 1.46 Example 7 9.85 1.84 Example 8 8.69 1.14 Example 9 9.68 0.85 Example 10 9.73 1.27 Embodiment 11 10.94 3.16 Comparative Example 1 0.45 0.22 Comparative Example 2 4.27 0.87 Comparative Example 3 3.86 2.25 4 5.87 1.69

[0083] According to the data in Table 3, we can see that:

[0084] (1) The initial peeling force of the solvent-free heating deviscosity-reducing glue obtained in Examples 1 to 11 is as high as 7.71 to 12.55 N / in, and the peeling force after deviscosity-reducing is as low as 1.02 to 3.16 N / in, which has an excellent heating deviscosity-reducing effect;

[0085] (2) By comparing the data of Example 1 and Comparative Examples 1 to 3, it can be seen that with the addition of the molecular weight regulator, the peeling force of the solvent-free heating viscosity-reducing glue first increases and then decreases. This is because the increase in the amount of molecular weight regulator added will cause the molecular weight of the glue after curing to gradually decrease, the wetting fluidity to increase, and the peeling force to gradually increase. However, when the amount of molecular weight regulator added is too much, the molecular weight of the glue is too small, and although the wettability is strong, the cohesion is poor and it is easy to draw, which eventually leads to a gradual decrease in the peeling force of the glue;

[0086] (3) By comparing the data of Example 1 and Comparative Example 4, it can be seen that when a carboxyl or amide-containing acrylic acid ester functional monomer is added to the glue, the peeling force of the glue on the glass can be significantly improved;

[0087] (4) Finally, by comparing the data of Example 1 and Example 11, it can be seen that when the molar amount of isocyanate groups is kept unchanged but the functionality is reduced from 3 to 2, although the crosslinking points of the glue do not decrease during high-temperature viscosity reduction, the network structure formed is insufficient, which will lead to a poor viscosity reduction effect of the glue.

[0088] The applicant declares that the present invention illustrates a solvent-free heating viscosity-reducing glue and its preparation method and use method through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A solvent-free heating viscosity-reducing glue, characterized in that: The solvent-free heating viscosity-reducing glue comprises the following components in parts by weight:

2. The solvent-free heating viscosity-reducing glue according to claim 1, characterized in that: The acrylic resin includes polyurethane acrylate and / or aliphatic polyester acrylate, preferably polyurethane acrylate, and further preferably polyurethane acrylate having a glass transition temperature not higher than -10°C.

3. The solvent-free heating viscosity-reducing glue according to claim 1 or 2, characterized in that: The acrylic acid ester structural monomer is a monofunctional acrylic acid ester structural monomer; Preferably, the glass transition temperature of the monofunctional acrylic ester structural monomer is not higher than 0°C; Preferably, the monofunctional acrylic ester structural monomer includes any one of isodecyl methacrylate, isodecyl acrylate, isooctyl acrylate, isooctyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, isononyl methacrylate, isononyl acrylate, tridecyl methacrylate, tridecyl acrylate, heptadecyl methacrylate, heptadecyl acrylate, octadecyl methacrylate, octadecyl acrylate, eicosyl methacrylate, eicosyl acrylate, isooctadecyl methacrylate, isooctadecyl acrylate, lauryl acrylate, tetrahydrofuran acrylate or ethoxyethoxyethyl acrylate, or a combination of at least two thereof.

4. The solvent-free heating viscosity-reducing glue according to any one of claims 1 to 3, characterized in that: The acrylate functional monomer is an acrylate monomer containing a carboxyl group and / or an amide group; Preferably, the acrylate functional monomer includes any one or a combination of at least two of acryloylmorpholine, dimethylacrylamide, diethylacrylamide or carboxyethyl acrylate; Preferably, the acrylic acid ester reactive monomers include hydroxy acrylic acid esters; Preferably, the acrylic acid ester reactive monomer includes any one of hydroxyethyl acrylate, hydroxypropyl acrylate or hydroxybutyl acrylate, or a combination of at least two thereof.

5. The solvent-free heating viscosity-reducing glue according to any one of claims 1 to 4, characterized in that: The photoinitiator includes any one of 1-hydroxycyclohexyl phenyl ketone, ethyl 2,4,6-trimethylbenzoylphenylphosphonate or 2-hydroxy-2-methyl-1-phenyl-1-propanone or a combination of at least two thereof; Preferably, the molecular weight regulator comprises a thiol molecular weight regulator.

6. The solvent-free heating viscosity-reducing glue according to any one of claims 1 to 5, characterized in that: The isocyanate comprises a polyisocyanate having a functionality not less than 3; Preferably, the polyisocyanate includes any one of toluene diisocyanate trimer, toluene diisocyanate trimer biuret, hydrogenated toluene diisocyanate trimer, hydrogenated toluene diisocyanate biuret, diphenylmethane diisocyanate trimer, diphenylmethane diisocyanate biuret, hydrogenated diphenylmethane diisocyanate trimer, hydrogenated diphenylmethane diisocyanate biuret, hexamethylene diisocyanate trimer, hexamethylene diisocyanate biuret, isophorone diisocyanate trimer or isophorone diisocyanate biuret, or a combination of at least two thereof, and more preferably hexamethylene diisocyanate trimer and / or hexamethylene diisocyanate biuret.

7. The solvent-free heating viscosity-reducing glue according to any one of claims 1 to 6, characterized in that: The blocking agent includes any one of small molecule alcohol, phenol, ketoxime or small molecule amine, or a combination of at least two of them.

8. A method for preparing the solvent-free heating viscosity-reducing glue according to any one of claims 1 to 7, characterized in that: The preparation method comprises: mixing acrylate structural monomers, acrylate functional monomers and acrylate reactive monomers under light-proof conditions, adding isocyanate for reaction, adding a blocking agent for blocking, and finally adding a photoinitiator, an acrylate resin and a molecular weight regulator for mixing to obtain the solvent-free heating viscosity-reducing glue.

9. A method for using the solvent-free heating viscosity-reducing glue according to any one of claims 1 to 7, characterized in that: The method of use comprises the following steps: (1) coating the solvent-free heating and viscosity-reducing glue on the substrate or release film to be bonded, and light curing to complete the bonding of the solvent-free heating and viscosity-reducing glue; (2) Heat-treating the solidified solvent-free heating viscosity-reducing glue obtained in step (1) to complete the stripping of the solvent-free heating viscosity-reducing glue.

10. The method of use according to claim 9, characterized in that: The energy of the light curing in step (1) is 300 to 1000 mJ / cm 2 ; Preferably, the heating temperature in step (2) is 130-150° C. Preferably, the heating time in step (2) is 10 to 20 minutes.

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