TWI700341B - Photosensitive ink composition - Google Patents

Abstract

A photosensitive ink composition is disclosed, which comprises: (A) 70wt% to 90 wt% of a urethane acrylate oligomer; (B) 2 wt% to 25 wt% of at least two kinds of cyclic acrylic monomers; (C) 0.1 wt% to 5wt % of at least one photoinitiator; and (D) 0.1 wt% to 1 wt% of a pigment.

Description

Photosensitive ink composition

The present invention relates to a photosensitive ink composition, especially a photosensitive ink composition with reworkability.

In the past, in the back-end manufacturing process of the display panel, black glue was manually applied to the side of the panel to protect the side of the panel and avoid light leakage from the side. However, manual implementation has the disadvantages of high cost and low efficiency. Nowadays, display panels tend to be lighter, thinner and narrower. When the panels become thinner and thinner, manual operations can easily cause panel damage. The glue method replaces traditional manual work and derives the technology of using black photosensitive ink with machine spraying.

However, due to factors such as hardware stability, software control ability, and personnel calibration, which affect the longitude of the spray path, the yield of the machine dispensing process is limited, and a large number of display panels that need to be scrapped are generated, which greatly increases production costs.

Therefore, in order to reduce the scrap rate of the display panel, it is a better solution to remove the defective photosensitive ink and spray new photosensitive ink again. However, the existing photosensitive inks, such as the Chinese Patent Publication No. CN106433492A, mainly consist of oligomers with polymerizable groups, reactive monomers, photoinitiators, dyes and additives, among which there are many reactive monomers. It is a linear acrylic monomer, and this type of photosensitive ink is prone to residual glue when stripped, which is not conducive to heavy industry. There is an urgent need to develop a novel photosensitive ink composition that can be sprayed with a machine, and is not easy to have residual glue when peeled off at the same time, and has the characteristics of reworkability, so as to prevent the display panel from reducing the yield due to scrap.

The main purpose of this disclosure is to provide a photosensitive ink composition that has the characteristics of being reworkable. Therefore, when the machine spraying longitude produces errors, the entire strip or the entire sheet of the cured ink can be peeled off, so that the display panel can be reused. In order to reduce the scrap rate of the display panel.

The photosensitive ink composition of the present disclosure may include: (A) 70% to 90% by weight of urethane acrylate oligomer; (B) 2% to 25% by weight of at least two cyclic acrylic monomers; (C) ) 0.1% to 8% by weight of at least one photoinitiator; and (D) 0.1% to 1% by weight of pigment.

In the photosensitive ink composition provided by the present disclosure, urethane acrylate oligomer (A) is used as the main component of the composition, and the free radicals generated by the photoinitiator (C) are transmitted to make at least two cyclic acrylic monomers The body (B) and the urethane acrylate oligomer are polymerized and crosslinked, and by adjusting the composition and content of at least two cyclic acrylic monomers (B), the photosensitive ink composition can be reworked and has no glue residue. In addition, the pigment (D) is used for coloring in the present disclosure, so that the photosensitive ink composition of the present disclosure has the effect of shielding light leakage on the display panel side after curing.

In the photosensitive ink composition of the present disclosure, the use of a cyclic acrylic monomer as a reactive monomer can avoid the occurrence of glue residue when the cured photosensitive ink composition is removed from the glass substrate. More specifically, the photosensitive ink composition of the present disclosure does not contain linear acrylic monomers. Therefore, the prepared photosensitive ink composition has the characteristics of reworkability and no glue residue.

其中，R₁、R₂及R₃係各自獨立為H或C_1-6烷基。 In the photosensitive ink composition of the present disclosure, the at least two cyclic acrylic monomers comprise 1 to 23 weight percent of the cyclic acrylic monomer a, and 1 to 23 weight percent of the cyclic acrylic monomer b. Wherein, the cyclic acrylic monomer a and the cyclic acrylic monomer b are selected from monomers represented by the following formulas (I-1), (I-2) and (I-3):

Wherein, R ₁ , R ₂ and R ₃ are each independently H or C _1-6 alkyl.

In the photosensitive ink composition of the present disclosure, in the cyclic acrylic monomer represented by formula (I-1), R ₁ can be H or C _1-6 alkyl, and R _{1 is} preferably H or C _1-3 alkane base. In an embodiment of the present disclosure, the cyclic acrylic monomer represented by formula (I-1) is isobornyl acrylate (IBOA).

In the photosensitive ink composition of the present disclosure, in the cyclic acrylic monomer represented by formula (I-2), R ₂ can be H or C _1-6 alkyl, and R _{2 is} preferably H or C _1-3 alkane base. In an embodiment of the present disclosure, the cyclic acrylic monomer represented by formula (I-2) is tetrahydrofurfuryl acrylate (THFA).

In the photosensitive ink composition of the present disclosure, in the cyclic acrylic monomer represented by formula (I-3), R ₃ can be H or C _1-6 alkyl, and R _{3 is} preferably H or C _1-3 alkane base. In an embodiment of the present disclosure, the cyclic acrylic monomer represented by formula (I-3) is glycidyl methacrylate (GMA).

In an embodiment of the present disclosure, the cyclic acrylic monomer a and the cyclic acrylic monomer b are cyclic acrylic monomers represented by formula (I-1) and formula (I-2), respectively.

In addition, the cyclic acrylic monomer in the present disclosure can also be used as a diluent. Therefore, the photosensitive ink composition of the present disclosure does not require additional solvents, which can achieve the effects of reducing costs, environmental pollution, or friendly operators.

In the photosensitive ink composition of the present disclosure, as measured according to ASTM D3759, the photosensitive ink composition has a ductility of 0 to 20%. Slight ductility is conducive to rework of the photosensitive ink composition, but too high ductility is not conducive to rework. Preferably, the photosensitive ink composition has a ductility of 0 to 15%.

In the photosensitive ink composition of the present disclosure, the type of photoinitiator (C) is not particularly limited, and at least one photoinitiator can be used for the reaction, for example, it can contain 2,4,6-trimethylbenzyl Diphenyl phosphine oxide or bis(2,4,6-trimethylbenzyl)phenyl phosphine oxide, but the present disclosure is not limited thereto. In an embodiment of this disclosure, the photoinitiator (C) is 2,4,6-trimethylbenzyl diphenyl phosphine oxide (Darocur TPO) and bis(2,4,6-trimethyl Benzyl) phenyl phosphine oxide (Irgacure 819).

In the photosensitive ink composition of the present disclosure, the type of the pigment (D) is not particularly limited, and at least one of any black dyes known in the art can be used. In an embodiment of the present disclosure, the pigment is carbon black.

The present disclosure uses cyclic acrylic monomers as reactive monomers. Therefore, the photosensitive ink composition will not form residual glue on the glass substrate after being reworked. In addition, the photosensitive ink composition has a proper range of ductility, and has the characteristics of being easy to rework, can maintain the integrity of the device, and is beneficial to reduce the rejection rate of the display panel.

The following are specific examples to illustrate the implementation of the present disclosure. Those familiar with the art can easily understand the other advantages and effects of the present disclosure from the content disclosed in this specification. The present disclosure can also be implemented or applied by other different specific embodiments, and various details in this specification can also be modified and changed according to different viewpoints and applications without departing from the spirit of the creation.

Unless otherwise stated in the context, the singular forms "a" and "the" used in the specification and the appended patent application may include one or plural entities.

Unless otherwise stated in the context, the term "or" used in the specification and the appended patent application usually includes the meaning of "and/or".

The present disclosure will be described in more detail through embodiments, but these embodiments are not intended to limit the scope of the present disclosure. Unless otherwise specified, in the following preparation examples, examples and comparative examples, the temperature is Celsius, and the parts and percentages are by weight. The relationship between parts by weight and parts by volume is like the relationship between kilograms and liters.

Preparation of photosensitive ink composition

Example 1

In the reaction vessel, add 2.5 g of reactive monomers isobornyl acrylate (IBOA), 2.5 g of tetrahydrofurfuryl acrylate (THFA) and photoinitiator powder (2,4,6-trimethylbenzyl two Phenyl phosphine oxide (TPO) 3g and bis(2,4,6-trimethylbenzyl)phenyl phosphine oxide (Irgacure 819) 2g), pre-dissolved with mechanical stirring, wait until the photoinitiator powder is fully dissolved Afterwards, 90 g of urethane acrylate oligomer and 0.25 g of carbon black were added, and the photosensitive ink composition of Example 1 was obtained by mechanical stirring until homogeneous.

Example 2 to Example 8

The photosensitive ink compositions of Example 2 to Example 8 were prepared according to the composition shown in Table 1 below and according to the steps of Example 1.

Comparative example 1 to comparative example 5

The photosensitive ink compositions of Comparative Example 1 to Comparative Example 5 were prepared according to the composition shown in Table 2 below and according to the steps of Example 1.

Curing sample preparation

Method 1: Use a spin coater to coat the photosensitive ink composition on the strengthened glass, adjust the appropriate rotation speed to control the film thickness to about 100μm, and then irradiate the 365nm LED to perform light curing to form the film. The resulting sample can be used for subsequent ductility testing.

Method 2: Use mechanical dispensing to spray the sides of the display panel with a spray thickness of about 300μm, and then use 365nm LED irradiation for light curing. The resulting sample can be used for subsequent residual glue test.

Ductility test

Refer to the ASTM D3759 test method, remove the film from the glass, cut into a 2.54×10cm long film for ductility test, fix the two ends of the long film on a tensile machine at a tensile speed of 80mm/min, Extend until the long film breaks, calculate the ductility, and record the results in Table 1 and Table 2.

Residual glue test

A physical heavy-duty test, that is, a cured sample coated on the side of the display panel by hand, and the residual glue is judged. The results are recorded in Table 1 and Table 2.

EM211: 2-(2-ethoxyethoxy)ethyl acrylate (EOEOEA)

EM215: Lauryl acrylate (LA)

As shown in the results of Examples 1 to 8, when the cyclic acrylic monomer is used as the reactive monomer, the obtained photosensitive ink composition will not form residue on the glass substrate during the test after curing. In contrast to Comparative Examples 1 to 3, when a linear acrylic monomer is used to partially or completely replace the cyclic acrylic monomer to prepare a photosensitive ink composition, the cured sample obtained will form a residue on the glass substrate when tested. In addition, when the urethane acrylate oligomer content is less than 70% by weight, as shown in Comparative Example 4 and Comparative Example 5, the cured sample obtained will form a residual glue on the glass substrate during the residual glue test, and will be stretched It has 23% and 42% ductility in the test. Excessive ductility will require more space or/and longer time for heavy work, which will result in increased costs. Therefore, compared with the photosensitive ink compositions of Examples 1 to 8, Comparative Example 4 and The photosensitive ink composition of Comparative Example 5 lacks industrial competitiveness.

Through the above residual glue and ductility test, it can be clearly found that after curing, the photosensitive ink composition using the cyclic acrylic monomer has an appropriate range of ductility, which is beneficial to heavy work, and does not produce residue. The situation of glue. Therefore, the photosensitive ink composition provided by the present disclosure can be used to protect the sides of a display panel or to avoid light leakage.

The above-mentioned embodiments are merely examples for the convenience of description, and the scope of rights claimed in this disclosure should be subject to the scope of the patent application, not limited to the above-mentioned embodiments.

Claims (9)

A photosensitive ink composition, comprising: (A) 70% to 90% by weight of urethane acrylate oligomer; (B) 2% to 25% by weight of at least two cyclic acrylic monomers; (C) 0.1 At least one photoinitiator in an amount of to 8 weight percent; and (D) a pigment in an amount of 0.1 to 1 weight percent; wherein the at least two cyclic acrylic monomers include cyclic acrylic monomer a and cyclic acrylic monomer b And the cyclic acrylic monomer a and the cyclic acrylic monomer b are selected from monomers represented by the following formulas (I-1), (I-2) and (I-3):

Wherein, R ₁ , R ₂ and R ₃ are each independently H or C _1-6 alkyl. The photosensitive ink composition according to item 1 of the patent application, wherein the at least two cyclic acrylic monomers comprise 1 to 23 weight percent of the cyclic acrylic monomer a, and 1 to 23 weight percent Cyclic acrylic monomer b. The photosensitive ink composition described in item 1 of the scope of patent application, wherein the monomer of the formula (I-1) is isobornyl acrylate. The photosensitive ink composition described in item 1 of the scope of patent application, wherein the monomer of the formula (I-2) is tetrahydrofurfuryl acrylate. The photosensitive ink composition described in item 1 of the scope of patent application, wherein the monomer of the formula (I-3) is glycidyl methacrylate. According to the photosensitive ink composition described in item 1 of the patent application, the at least two cyclic acrylic monomers are monomers represented by formulas (I-1) and (I-2). The photosensitive ink composition described in item 1 of the scope of patent application, wherein the photosensitive ink composition has a ductility of 0 to 20%. The photosensitive ink composition described in item 1 of the scope of patent application, wherein the photosensitive ink composition has a ductility of 0 to 15%. The photosensitive ink composition according to item 1 of the scope of patent application, wherein the at least one photoinitiator comprises 2,4,6-trimethylbenzyl diphenyl phosphine oxide or bis(2,4,6 -Trimethylbenzyl) phenyl phosphine oxide.