Radiation curing pressure-sensitive adhesive composition for protective film and application of radiation curing pressure-sensitive adhesive composition

Abstract

The invention belongs to the field of radiation curing pressure-sensitive adhesives, and discloses a radiation curing protective film adhesive composition as well as preparation and application thereof. The composition is prepared from the following components in parts by mass: 30 to 70 parts of polyurethane acrylate, 10 to 40 parts of special (methyl) acrylate monomer, 10 to 40 parts of other monofunctional (methyl) acrylate or acrylamide monomer, 0 to 5 parts of bifunctional or polyfunctional (methyl) acrylate monomer, 0 to 5 parts of tackifying resin and 0.5 to 5 parts of photoinitiator. According to the pressure-sensitive adhesive composition for the UV curing protective film adhesive tape, the preparation method is simple, and the comprehensive performance of the composition is improved by optimizing the formula; the protective film adhesive tape prepared on the basis of the pressure-sensitive adhesive composition has higher curing speed and higher peel strength and annular initial adhesion on the premise of keeping excellent exhaust property, and the problem that the properties cannot be considered at the same time in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of radiation curing materials, in particular to a UV curing protective film tape and a manufacturing method thereof. Background Art

[0002] Protective film tape is a special adhesive tape widely used in various industries. It is mainly used to protect the surface of various objects to prevent dust, scratches and damage. It usually uses plastic films such as PET, PO, PU or PVC as the substrate, and is coated with a layer of special pressure-sensitive adhesive on the substrate, which can adhere well to the surface of the object, but is easy to remove without leaving traces. At present, protective film tape is mainly used in the fields of electronic component protection, steel protection, automotive interior protection, furniture and household appliances protection.

[0003] At present, the common method of protective film tape is mainly solvent-based. The glue of solvent-based protective film tape contains a large amount of volatile organic compounds (VOC), and the energy consumption in the production process is large and the production cycle is long. In addition to solvent-based, the production methods of tape also include hot melt and radiation curing. Although hot melt tape has the characteristics of solvent-free and high production efficiency, its adhesive layer is often not resistant to high temperature and solvents, and the high coating temperature limits its application on certain substrates (such as PVC). Radiation curing is a technology that cross-links polymers through electromagnetic radiation such as ultraviolet light (UV) or electron beam (EB). The characteristics of this technology are that it can be coated at room temperature, quickly cured, does not require solvent or water evaporation, and does not require an oven or other heating equipment. It can greatly reduce production costs and improve production efficiency, and will not produce harmful gases or pollute the environment.

[0004] The components of UV curing pressure sensitive adhesive include prepolymer resin, active diluent, photoinitiator and other additives. Among them, the active diluent used for protective film tape is mainly (meth) acrylate monomer, and mainly soft monomer with low glass transition temperature. Such soft monomer can provide better exhaust performance, mainly including (meth) butyl acrylate, (meth) acrylate-2-ethylhexyl ester, (meth) acrylate lauryl ester, ethoxyethoxyethyl acrylate, etc. However, the addition of such monomers often leads to disadvantages such as reduced curing speed and reduced peel strength, which limits the production speed and application field of UV curing protective film tape.

[0005] Therefore, it is necessary to provide a pressure-sensitive adhesive composition with fast curing speed, high peel strength and good exhaust performance to solve the problems of slow curing speed and low peel strength of current UV curing protective film tapes. Summary of the invention

[0006] In view of the above technical problems, the main purpose of the present invention is to provide a UV curable protective film tape composition and a method for manufacturing the same.

[0007] The main purpose of the present invention is achieved through the following solutions:

[0008] The first aspect of the present invention is to provide a pressure-sensitive adhesive composition for UV-curable protective film tape, comprising the following raw materials in parts by weight:

[0009]

[0010] The structure of the special (meth)acrylate monomer is Wherein R=H or CH3, n=1~10; preferably R=H, n=1~3; the special (meth)acrylate monomer is selected from One or a combination of .

[0011] Furthermore, the polyurethane acrylate is a polyurethane acrylate containing 1 to 3 photosensitive group functionalities; the photosensitive group is a (meth)acrylate group; preferably, the polyurethane acrylate is a polyurethane acrylate containing 2 photosensitive groups; the polyurethane acrylate may be a mixture of one or more.

[0012] In some preferred embodiments of the present invention, the polyurethane acrylate may be one or more of CN 8881NS, CN9782, CN8887NS, CN8888NS, CN8895NS or CN9021 produced by Sartomer.

[0013] The monofunctional (meth)acrylate monomer is a monomer containing only one (meth)acrylate group.

[0014] Furthermore, the monofunctional (meth)acrylate monomer is a mixed monomer consisting of at least one soft monomer with a lower homopolymer glass transition temperature and at least one hard monomer with a higher homopolymer glass transition temperature.

[0015] Preferably, the soft monomer is selected from one or a combination of (meth)acrylate monomers such as n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, decadecyl (meth)acrylate, lauryl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofuran (meth)acrylate, benzyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and ethoxyethoxyethyl acrylate.

[0016] Preferably, the hard monomer is selected from one or a combination of (meth)acrylate (acrylamide) monomers such as isobornyl (meth)acrylate, cyclotrimethylolpropane formal (meth)acrylate, acrylamide, and N,N-dimethylacrylamide.

[0017] Furthermore, the difunctional or multifunctional (meth)acrylate monomer is a monomer containing two or more (meth)acrylate groups.

[0018] Preferably, the difunctional or multifunctional (meth)acrylate monomer is selected from one or a combination of 1,6-hexanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0019] Furthermore, the tackifying resin is terpene resin, rosin resin, petroleum resin or other synthetic resins; further preferably, the tackifying resin is rosin resin or modified rosin resin;

[0020] Preferably, the photoinitiator is at least one of an α-hydroxyketone photoinitiator and an acylphosphine oxide photoinitiator; more preferably, it is at least one of Ciba's Darocur 1173 photoinitiator, Ciba's Darocur MBF photoinitiator, BASF's Irgacure 184 photoinitiator, BASF's Irgacure 2022 photoinitiator, BASF's Irgacure 127 photoinitiator and BASF's Lucirin TPO photoinitiator.

[0021] The second aspect of the present invention is to provide a method for preparing the pressure-sensitive adhesive composition for the UV-curable protective film tape, comprising: mixing 30 to 70 parts of polyurethane acrylate, 10 to 40 parts of special (meth)acrylate monomers, 20 to 40 parts of monofunctional (meth)acrylate monomers, 0 to 5 parts of multifunctional (meth)acrylate monomers, 0 to 5 parts of tackifying resin, and 0.5 to 5 parts of photoinitiator, and then stirring and dispersing them evenly to obtain the UV-curable protective film tape adhesive composition.

[0022] The third aspect of the present invention is to provide a UV curable protective film tape, wherein the UV curable protective film tape has both a fast curing speed and good exhaust performance.

[0023] The present invention also provides a method for preparing the UV curable protective film tape, which is based on the pressure sensitive adhesive composition described above; the preparation method comprises the following steps:

[0024] S1: firstly, coating the pressure-sensitive adhesive composition on a plastic film using a wire rod to obtain a wet film;

[0025] S2: The plastic film coated with the pressure-sensitive adhesive composition obtained in S1 is then UV cured to obtain a UV-curable protective film tape.

[0026] Further, the wet film thickness in step S1 is 3 to 50 μm, more preferably 5 to 10 μm;

[0027] Furthermore, the plastic film used in step S1 includes PET film, PVC film, PO film, and PU film;

[0028] Furthermore, the UV light energy in step S2 is preferably 500 to 3000 mJ / cm 2 , more preferably 1000 to 2500 mJ / cm 2 .

[0029] The present invention also provides the application of the pressure-sensitive adhesive composition or the UV curing protective film tape in the field of electronic-grade pressure-sensitive adhesive protective films, using the special (meth)acrylate monomer provided by the present invention, and having a faster curing speed and good exhaust performance.

[0030] Beneficial effects:

[0031] Compared with the prior art, the technical solution of the present application has at least the following advantages:

[0032] The pressure-sensitive adhesive composition for UV-curable protective film tape provided by the present invention has a simple preparation method, and the comprehensive performance of the composition is improved by optimizing the formula; the special (meth) acrylate monomer structure in the pressure-sensitive adhesive composition provided by the present invention has an ethoxylated The structure provides good exhaust properties for the tape, while the hydroxyl group (-OH) in the structure enables the monomer to have a faster UV curing speed and higher bonding strength.

[0033] The invention also provides a protective film tape prepared based on the pressure-sensitive adhesive composition. The product has a faster curing speed while maintaining excellent air-discharging properties, and also has higher peel strength and annular initial adhesion, thus overcoming the problem in the prior art that these properties cannot be taken into account at the same time. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Performance testing method:

[0036] (1) UV curing speed test

[0037] Test instrument: Total reflection Fourier infrared spectrometer.

[0038] Test sample: Pressure sensitive adhesive under different UV energy gradient irradiation.

[0039] Test method: The infrared spectra of the pressure-sensitive adhesive under different UV energy gradient irradiation are tested by total reflection Fourier transform infrared spectrometer, and the degree of weakening of the double bond peak is calculated by infrared analysis software to represent the conversion rate of the pressure-sensitive adhesive.

[0040] Test results: Double bond conversion rate of pressure-sensitive adhesive under different UV energy gradient irradiation, unit: %.

[0041] (2) 180° peel force test

[0042] Test equipment: Tensile tester or similar instrument, whose fixture can peel off pressure-sensitive materials at 180°, peeling speed 300mm / min, accuracy ±2%, test plate made of stainless steel with smooth surface. A standard pressure roller (2kg);

[0043] Test sample: Take a test strip from the prepared pressure-sensitive adhesive for the protective film, with a width of 25 mm; at least 200 mm long along the instrument direction, with a clean and straight cut. At least 3 strips of each material should be taken for testing;

[0044] Test conditions: temperature 23℃±2℃, 50%RH±5%RH;

[0045] Test steps: Place the protective film with the pressure-sensitive adhesive test strip facing downward, and apply the strip to the clean test board with slight finger pressure. Use a pressure roller to press back and forth twice at a speed of about 500mm / second to make the adhesive surface closely contact the test board. After the test strip is applied, leave it for 20 minutes before testing again. Adjust the peeling angle to 180°, set the speed to 300mm / min, and start the test;

[0046] Test results: The peel force is expressed in N / 25mm, and the average value is taken for each test strip.

[0047] (3) Ring initial adhesion test

[0048] Testing instrument: Ring initial adhesion tester;

[0049] Test sample: Take a test strip from the prepared pressure-sensitive adhesive for the protective film, with a width of 25 mm; at least 200 mm long along the instrument direction, with a clean and straight cut. At least 3 strips of each material should be taken for testing;

[0050] Test conditions: temperature 23℃±2℃, 50%RH±5%RH;

[0051] Test steps: Connect the two ends of the protective film with the pressure-sensitive adhesive test strip with the adhesive surface facing outward, fix the connected parts with the clamp of the ring initial adhesion tester, then move down 40mm at a speed of 300mm / min, pause for 3s, and then move up 40mm at a speed of 300mm / min.

[0052] Test results: Read the maximum value in the annular initial adhesion test curve, in units of N / 25mm, and take the average value for each test strip.

[0053] (4) Wetting and degassing test

[0054] In the performance test method (2) of the loop initial adhesion test, the wetting and degassing ability of the tape is represented by the percentage of the actual bonding area of ​​the tape when the tape is paused for 3 seconds to the maximum bonding area (25mm*25mm), in %.

[0055] The present invention is described in detail below. The raw materials and the amounts of raw materials used in each example are shown in Table 1.

[0056] Table 1: Allocation ratio of each group in the embodiment

[0057]

[0058] Example 1

[0059] A method for preparing a UV curable protective film tape, the method comprising the following steps:

[0060] 50 parts of difunctional polyurethane acrylate (CN 8888NS), 30 parts of special (meth)acrylate monomer (R=H, n=1), 5 parts of hydroxyethyl acrylate (HEA), 5 parts of isobornyl acrylate (IBOA), 5 parts of 1,6-hexanediol diacrylate (HDDA), and 5 parts of modified rosin resin were mixed and stirred and dispersed at a speed of 2000 rpm for 30 minutes using a disperser to prepare the UV-curable protective film tape composition.

[0061] A method for preparing a UV curable protective film tape comprises the following steps:

[0062] S1: First, the UV curable protective film tape glue is coated on the plastic film with a wire rod to obtain a wet film with a thickness of 8 μm;

[0063] S2: The plastic film coated with the liquid coating obtained in S1 is then UV cured to obtain a protective film tape. The UV energy used for the tests of peel strength, loop initial adhesion, and exhaust performance is 2000 mJ / cm 2 .

[0064] Example 2

[0065] A method for preparing a UV curable protective film tape, the method comprising the following steps:

[0066] 60 parts of difunctional polyurethane acrylate (CN 8888NS), 20 parts of special (meth)acrylate monomer (R=H, n=2), 5 parts of hydroxyethyl acrylate (HEA), 5 parts of isobornyl acrylate (IBOA), 5 parts of 1,6-hexanediol diacrylate (HDDA), and 5 parts of modified rosin resin were mixed and stirred and dispersed at a speed of 2000 rpm for 30 minutes using a disperser to prepare the UV-curable protective film tape composition.

[0067] A method for preparing a UV curable protective film tape comprises the following steps:

[0068] S1: First, the UV curable protective film tape glue is coated on the plastic film with a wire rod to obtain a wet film with a thickness of 8 μm;

[0069] S2: The plastic film coated with the liquid coating obtained in S1 is then UV cured to obtain a protective film tape. The UV energy used for the tests of peel strength, loop initial adhesion, and exhaust performance is 2000 mJ / cm 2 .

[0070] Example 3

[0071] A method for preparing a UV curable protective film tape, the method comprising the following steps:

[0072] 70 parts of difunctional polyurethane acrylate (CN 8888NS), 10 parts of special (meth)acrylate monomer (R=H, n=3), 5 parts of hydroxyethyl acrylate (HEA), 5 parts of isobornyl acrylate (IBOA), 5 parts of 1,6-hexanediol diacrylate (HDDA), and 5 parts of modified rosin resin were mixed and stirred and dispersed at a speed of 2000 rpm for 30 minutes using a disperser to prepare the UV-curable protective film tape composition.

[0073] A method for preparing a UV curable protective film tape comprises the following steps:

[0074] S1: First, the UV curable protective film tape glue is coated on the plastic film with a wire rod to obtain a wet film with a thickness of 8 μm;

[0075] S2: The plastic film coated with the liquid coating obtained in S1 is then UV cured to obtain a protective film tape. The UV energy used for the tests of peel strength, loop initial adhesion, and exhaust performance is 2000 mJ / cm 2 .

[0076] Comparative Example 1

[0077] A method for preparing a UV curable protective film tape, the method comprising the following steps:

[0078] 50 parts of difunctional polyurethane acrylate (CN 8888NS), 30 parts of 2-ethylhexyl acrylate (2-EHA), 5 parts of hydroxyethyl acrylate (HEA), 5 parts of isobornyl acrylate (IBOA), 5 parts of 1,6-hexanediol diacrylate (HDDA), and 5 parts of modified rosin resin were mixed, and stirred and dispersed at a speed of 2000 rpm for 30 minutes using a disperser to prepare the UV-curable protective film tape composition.

[0079] A method for preparing a UV curable protective film tape comprises the following steps:

[0080] S1: First, the UV curable protective film tape glue is coated on the plastic film with a wire rod to obtain a wet film with a thickness of 8 μm;

[0081] S2: The plastic film coated with the liquid coating obtained in S1 is then UV cured to obtain a protective film tape. The UV energy used for the tests of peel strength, loop initial adhesion, and exhaust performance is 2000 mJ / cm 2 .

[0082] Comparative Example 2

[0083] A method for preparing a UV curable protective film tape, the method comprising the following steps:

[0084] 50 parts of difunctional polyurethane acrylate (CN 8888NS), 30 parts of ethoxyethoxyethyl acrylate (EOEOEA), 5 parts of hydroxyethyl acrylate (HEA), 5 parts of isobornyl acrylate (IBOA), 5 parts of 1,6-hexanediol diacrylate (HDDA), and 5 parts of modified rosin resin were mixed, and stirred and dispersed at a speed of 2000 rpm for 30 minutes using a disperser to prepare the UV-curable protective film tape composition.

[0085] A method for preparing a UV curable protective film tape comprises the following steps:

[0086] S1: First, the UV curable protective film tape glue is coated on the plastic film with a wire rod to obtain a wet film with a thickness of 8 μm;

[0087] S2: The plastic film coated with the liquid coating obtained in S1 is then UV cured to obtain a protective film tape. The UV energy used for the tests of peel strength, loop initial adhesion, and exhaust performance is 2000 mJ / cm 2 .

[0088] Performance test results:

[0089] The pressure-sensitive adhesive tapes obtained in Examples 1-3 of the present invention and Comparative Examples 1-2 were tested for curing speed (double bond conversion rate), 180° peel strength, loop initial tack, air venting, etc. The test results are shown in Table 2.

[0090] Table 2 Performance test of embodiments and comparative examples

[0091]

[0092]

[0093] From the test results in Table 2, it can be seen that the embodiments 1 to 3 of the present invention have a 2 The double bond conversion rate reaches more than 95% under UV curing energy of 1500mJ / cm 2 When the curing temperature is 1000mJ / cm 2 When the temperature is 2000mJ / cm2, the rate is only 92% and 91% respectively. 2 In contrast, the pressure-sensitive adhesive composition provided by the present invention has a faster curing speed. At the same time, the degassing properties of Examples 1 to 3 can basically achieve the effects of Comparative Examples 1 to 2, and have higher peel strength and annular initial adhesion, and can be applied in a wider range of fields.

[0094] The pressure-sensitive adhesive composition for UV-curable protective film tape provided by the present invention has a faster curing speed while maintaining the exhaust property, and also has higher peel strength and annular initial adhesion, thus overcoming the problem in the prior art that these properties cannot be taken into account at the same time.

[0095] The above are only preferred embodiments of the present invention, which do not limit the protection scope of the present invention. For those skilled in the art, the present invention may have various modifications and changes. Within the spirit and principle of the present invention, changes, modifications, replacements, integrations and parameter changes to these embodiments by conventional substitutions or capable of achieving the same functions without departing from the principles and spirit of the present invention all fall within the protection scope of the present invention.

Claims

1. A pressure-sensitive adhesive composition for UV-curable protective film tape, characterized in that: The invention comprises the following raw materials in parts by weight: The structure of the special (meth)acrylate monomer is Wherein R is H or CH3, and n=1-10; preferably, R is H, and n=1-3.

2. The pressure-sensitive adhesive composition for UV-curable protective film tape according to claim 1, characterized in that: The polyurethane acrylate is a polyurethane acrylate containing 1 to 3 photosensitive group functionalities; the photosensitive group is a (meth)acrylate group; And / or, the monofunctional (meth)acrylate monomer is a mixed monomer consisting of at least one soft monomer with a lower homopolymer glass transition temperature and at least one hard monomer with a higher homopolymer glass transition temperature.

3. The pressure-sensitive adhesive composition for UV-curable protective film tape according to claim 2, characterized in that: The soft monomer is selected from one or a combination of (meth)acrylate monomers such as n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, deca (meth)acrylate, lauryl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofuran (meth)acrylate, benzyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, ethoxyethoxyethyl acrylate, etc.; And / or, the hard monomer is selected from one or a combination of (meth)acrylate (acrylamide) monomers such as isobornyl (meth)acrylate, cyclotrimethylolpropane formal (meth)acrylate, acrylamide, N,N-dimethylacrylamide, etc.

4. The pressure-sensitive adhesive composition for UV-curable protective film tape according to claim 1, characterized in that: The difunctional or multifunctional (meth)acrylate monomer is selected from one or a combination of 1,6-hexanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

5. The pressure-sensitive adhesive composition for UV-curable protective film tape according to claim 1, characterized in that: The tackifying resin is preferably rosin resin or modified rosin resin; And / or, the photoinitiator includes an α-hydroxyketone photoinitiator and an acylphosphine oxide photoinitiator; preferably at least one of Ciba's Darocur 1173 photoinitiator, Ciba's Darocur MBF photoinitiator, BASF's Irgacure 184 photoinitiator, BASF's Irgacure 2022 photoinitiator, BASF's Irgacure 127 photoinitiator and BASF's Lucirin TPO photoinitiator.

6. The method for preparing the pressure-sensitive adhesive composition for UV-curable protective film tape according to any one of claims 1 to 5, characterized in that: The steps include: 30 to 60 parts of polyurethane acrylate, 10 to 40 parts of special (meth)acrylate monomer, 20 to 40 parts of monofunctional (meth)acrylate monomer, 0 to 5 parts of multifunctional (meth)acrylate monomer, 0 to 5 parts of tackifying resin and 0.5 to 5 parts of photoinitiator are mixed and stirred and dispersed evenly to prepare the UV curable protective film tape adhesive composition.

7. A method for preparing a UV curable protective film tape, characterized in that: Using the pressure-sensitive adhesive composition described in any one of claims 1 to 5; the preparation method comprises the following steps: S1: firstly, coating the pressure-sensitive adhesive composition on a plastic film using a wire rod to obtain a wet film; S2: The plastic film coated with the pressure-sensitive adhesive composition obtained in S1 is then UV cured to obtain a UV-curable protective film tape.

8. The pressure-sensitive protective film tape according to claim 7, characterized in that: The wet film thickness in step S1 is 3 to 50 μm, more preferably 5 to 10 μm; The plastic film used in step S1 includes PET film, PVC film, PO film, and PU film.

9. The pressure-sensitive protective film tape according to claim 7, characterized in that: The UV light energy in step S2 is preferably 500 to 3000 mJ / cm 2 .

10. Use of the pressure-sensitive adhesive composition according to any one of claims 1 to 5, or the UV-curable protective film tape according to any one of claims 7 to 9 in the field of electronic-grade pressure-sensitive adhesive protective films.

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