GLASS FOR LASER PROCESSING AND METHOD FOR PRODUCING PERFORATED GLASS USING SAME

• US 20180029924A1
• Filed: 02/03/2016
• Published: 02/01/2018
• Est. Priority Date: 02/10/2015
• Status: Active Grant

• Current Assignee: Nippon Sheet Glass Company Limited
• Original Assignee: Nippon Sheet Glass Company Limited
• Inventors: INOUE, Teruhide, KURACHI, Junji
• Granted Patent: US 10,717,670 B2
• Time in Patent Office: Days
• CPC Class Codes: B23K 2103/54 Glass
• CPC Class Codes: B23K 26/0006 taking account of the properties of the material involved B23K26/32, B23K26/40 take precedence
• CPC Class Codes: B23K 26/0648 comprising lenses
• CPC Class Codes: B23K 26/352 for surface treatment
• CPC Class Codes: B23K 26/53 for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks
• CPC Class Codes: B23K 26/70 Auxiliary operations or equipment
• CPC Class Codes: B81C 1/00595 Control etch selectivity
• CPC Class Codes: C03B 33/0222 Scoring using a focussed radiation beam, e.g. laser
• CPC Class Codes: C03C 15/00 Surface treatment of glass, not in the form of fibres or filaments, by etching etching or surface-brightening compositions, in general C09K13/00
• CPC Class Codes: C03C 23/0025 by a laser beam
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/093 containing zinc or zirconium
• CPC Class Codes: C03C 3/095 containing rare earths
• CPC Class Codes: C03C 4/0071 for laserable glass

Abstract

The present invention provides a glass composition that allows holes with a circular contour and a smooth inner wall to be formed by a collective micro-hole-forming process using a combination of modified portion formation by ultraviolet laser irradiation and etching, the glass composition being adapted for practical continuous production. The present invention relates to a glass for laser processing, the glass including a metal oxide serving as a coloring component, the glass having a glass composition including, in mol %: 45.0%≦SiO₂≦68.0%; 2.0%≦B₂O₃≦20.0%; 3.0%≦Al₂O₃≦20.0%; 0.1%≦TiO₂≦5.0%; and 0%≦ZnO≦9.0%, wherein a relationship of 0≦Li₂O+Na₂O+K₂O<2.0% is satisfied.

Claims

1. A glass for laser processing, the glass comprising a metal oxide serving as a coloring component, the glass having a glass composition comprising, in mol %:

45.0%≦

SiO₂≦

68.0%;

2.0%≦

B₂O₃≦

20.0%;

3.0%≦

Al₂O₃≦

20.0%;

0.1%≦

TiO₂≦

5.0%; and

0%≦

ZnO≦

9.0%,

wherein a relationship of 0≦

Li₂O+Na₂O+K₂O<

2.0% is satisfied.

2. The glass for laser processing according to claim 1, wherein a relationship of 1.0%≦

ZnO≦

8.0% is satisfied.

3. The glass for laser processing according to claim 1, wherein the metal oxide serving as a coloring component comprises an oxide of at least one metal selected from the group consisting of Fe, Ce, Bi, W, Mo, Co, Mn, Cr, V, and Cu.

4. The glass for laser processing according to claim 1, wherein

the glass composition comprises, in mol %:

45.0%≦

SiO₂≦

66.0%;

7.00%≦

B₂O₃≦

17.0%;

7.0%≦

Al₂O₃≦

13.0%;

0.1%≦

TiO₂≦

4.0%; and

0%≦

ZnO≦

9.0%, and

the following relationships are satisfied;

58.0%≦

SiO₂+B₂O₃≦

76.0%;

6.0%≦

MgO+CaO+SrO+BaO≦

25.0%; and

0≦

Li₂O+Na₂O+K₂O<

2.0%.

5. The glass for laser processing according to claim 2, wherein

the glass composition comprises, in mol %:

45.0%≦

SiO₂≦

66.0%;

7.0%≦

B₂O₃≦

17.0%;

7.0%≦

Al₂O₃≦

13.0%;

0.1%≦

TiO₂≦

4.0%; and

1.0%≦

ZnO≦

8.0%, and

the following relationships are satisfied;

58.0%≦

SiO₂+B₂O₃≦

76.0%;

6.0%≦

MgO+CaO+SrO+BaO≦

25.0%; and

0≦

Li₂O+Na₂O+K₂O<

2.0%.

6. The glass for laser processing according to claim 1, wherein the metal oxide serving as a coloring component comprises, in mol % relative to the glass composition:

(I) 0.01%≦

Fe₂O₃≦

0.4%;

(II) 0.1%≦

CeO₂≦

2.0%;

or

(III) 0.01%≦

Fe₂O₃≦

0.4% and 0.1%≦

CeO₂≦

2.0%.

7. The glass for laser processing according to claim 4, wherein the glass composition further comprises, in mol %:

2.0%≦

MgO≦

10.0%;

1.0%≦

CaO≦

10.0%;

1.0%≦

SrO≦

10.0%; and

0%≦

BaO≦

6.0%.

8. The glass for laser processing according to claim 4, wherein the glass composition further comprises, in mol %:

3.0%≦

MgO≦

10.0%;

2.0%≦

CaO≦

10.0%;

2.0%≦

SrO≦

10.0%; and

0%≦

BaO≦

6.0%.

9. The glass for laser processing according to claim 1, wherein the glass composition further comprises, in mol %:

0.1%≦

ZrO₂≦

7.0%;

0.1%≦

Ta₂O₅≦

7.0%;

or

0.1%≦

Nb₂O₅≦

7.0%.

10. The glass for laser processing according to claim 1, further comprising a refractive index modifying component.

11. The glass for laser processing according to claim 10, wherein the refractive index modifying component comprises, in mol % relative to the glass composition:

0.1%≦

La₂O₃≦

7.0%;

or

0.1%≦

Bi₂O₃≦

7.0%.

12. The glass for laser processing according to claim 1, having a coefficient of thermal expansion of 60×

10<sup>−

7</sup>/°

C. or less.

13. The glass for laser processing according to claim 1, having an absorption coefficient α

of 3 to 40/cm.

14. A method for producing a perforated glass, comprising the steps of:

(i) irradiating an area of the glass for laser processing according to claim 1 with a laser pulse focused by a lens, thereby forming a modified portion in the irradiated area; and

(ii) etching at least the modified portion using an etchant, thereby forming a hole in the glass for laser processing.