GB2109395A

GB2109395A - Post emulsifiable fluorescent penetrant

Info

Publication number: GB2109395A
Application number: GB08132644A
Authority: GB
Inventors: John P Jones
Original assignee: Purex Corp
Current assignee: Purex Corp
Priority date: 1981-10-29
Filing date: 1981-10-29
Publication date: 1983-06-02

Abstract

A post emulsifiable penetrant composition for applications and entry into flaws in solid surfaces consists essentially of a) a first solvent ingredient comprising a high boiling point aromatic hydrocarbon, b) a second solvent ingredient selected from the group that includes di-phthalates and diesters, e.g. dioctyl phthalate or sebecate c) epoxidized material selected from the group that consists of epoxidized esters, oils and resins, d) fluorescent dye e.g. Hudson yellow or Fluoral 7GA, and e) fluorescent brightener e.g. 4-methyl- 7-dimethylamine or 7-diethylamino- 4-methyl coumarin.

Description

SPECIFICATION Post emulsifiable fluorescent penetrant This invention relates generally to fluorescent penetrant compositions, and particularly to heat stable compositions of this class.

Many type penetrants have in the past been used to locate flaws of discontinuities in metallic and non-metallic surfaces. The usual method of application isto apply the penetrantto the surface and after a suitable time the excess penetrant is removed by washing with a suitable solvent system or mechanically by wiping with a cloth or other absorbent material. Flaws are subsequently revealed by a seepage of the penetrant from the crevice or cavity.

Various agents have been added to the penetrant to increase the visibility of the seepage. These include ordinarily visible dyes, and fluorescent dyes. Absorbent powders are often applied to the surface of the article to absorb some of the dye and thus to increase the visibility of the flaw.

Fluorescent type penetrants which are currently available tend rapidly to lose brightness on metal surfaces when exposed to temperatures greater than about 140"F; and typically such penetrants lose about 75% or more brightness in about 30 minutes.

Accordingly, minute flaws or cracks in the metal surface can and do go undetected, in many cases due to rapid fading. The term "brightness" as used herein refers to visibility under ultraviolet light It is therefore desired to provide a solution to the above problem through the provision of an improved penetrant composition, or class of compositions, which retain desired brightness and typically lose less than 50% of their brightness under the same temperature and time conditions wherein prior fluorescent penetrants lose 75% or more of their brightness.

The present invention accordingly provides a post emulsifiable penetrant composition for application and entry into flaws in solid surfaces, consisting essentially of a) a first solvent ingredient comprising a high boiling point aromatic hydrocarbon, b) a second solvent ingredient selected from the group that includes di-phthalates and diesters, c) epoxidized material selected from the group that consists of epoxidized esters, oils and resins, d) fluorescent dye, and e) fluorescent brightener.

It has been found that the higher boiling point aromatic solvent serves to reduce viscosity of the formulation and provides heat stability. The viscosity reducing property of the aromatic solvent is important due to the viscosity increasing property of the epoxidized vegetable oil ingredient; however the vegetably oil serves to provide desired heat stability.

As respects the aromatic solvent, it consists principally of substituted benzenes and bicyclic aromatics, examples being listed as follows: Commercial Identification Manufacturer PANASOLAN-2K Amoco Chemical Corp.

PANASOL AN-3 Amoco Chemical Corp.

Amsco-Solv E 95 Union Oil Company, California Hi sol 4-1 Ashland Chemical Company Chartersol 4-P Charter International Oil Company Aromatic Solvent R Union Oil Company Physical characteristics of the aromatic solvent are: initial boiling point ranging from 350"F to 450"F (ASTM D-86); end boiling point ranging from 530"F to 600"F; and aromatic content from 75% to 100%.

(ASTM D-1319).

PANASOL is a Registered Trade Mark.

As respect the second solvent ingredient, it preferably consists of dioctyl phthalate (also known as di(2-ethylhexyl phthalate). Other usable phthalates include: diethyl phthalate, dibutyl phthalate, diisodecyl phthalate, diisooctyl phthalate, and di (n-octyl, N-decyl) phthalate. In general, the higher molecular weight phthalates have better heat stability than the lower molecular weight phthalates.

Other diesters, such as adipates, and sebecates (e.g. dioctyl sebecate) may be used, but at some sacrifice of heat stability.

The epoxidized ingredient imparts heat resistance, and consists of an epoxidized ester or oil. A preferred material is epoxidized soybean oil (vegetable oil) such as DRAPEX 6.8, for example, a product of Witco Chemical Co.

Other examples are: Commercial Identification Manufacturer FLEXOL PLASTICIZER LOE Union Carbide Company (an epoxidized linseed oil) DRAPEX 3.2 Witco Chemical Company (an octyl stearate epoxy) DRAPEX4.4 Witco Chemical Company (an octyl tallate epoxy) MONOPLEX S-73 (epoxy ester) Rohm and Hass Company PARAPLEX G-62 Rohm and Haas Company Also, liquid epoxy resins can be used to impart heat stability. An example is BAKELITE ERL 4289, a cycloaliphatic epoxy resin, obtainable from the Union Carbide Company.

BAKELITE is a Registered Trade Mark.

A typical formulation is as given in the following table: TABLE 1 Ingredient Range Preferred (%bywt) O/obywt) high boiling point 1-40 23.0 aromatic solvent (example: PANASOLAN-3) di-phthalate solvent 20-80 54.0 or di-ester solvent (example: dioctyl phthalate) epoxidized material 10-25 18.0 (example: DRAPEX 6.8) Fluorescent dye 0.1-3.0 1.0 (example: a naphthalimide such as Hudson yellow) fluorescent brightner 0.1-4.5 4.0 (example:Hiltamine Arctic White Sol, or other coumarin derivative, or MDAC It is found that without epoxidized material in the composition, the fluorescent dye rapidly fades in presence of heat over 1 30 F. Substitute fluorescent dyes include naphthalimide types such as Fluoral 7GA of GAF Company or Hudson yellow from Day Glo Color Corporation together with a fluorescent brightening agent such as 4-methyl -7-dimethylamine-coumarin (MDAC) or 7-diethylamino - 4 - methyl coumarin, e.g. Hiltamine artic white SOL of Hilton Davis Corp.

Hiltamine is a Registered Trade Mark.

The following formulas are usable, as examples: FORMULA 1 Ingredients % by weight Panasol AN3 10.0 di ethyl phthalate 27.0 di octyl phthalate 47.0 Drapex 6.8 13.5 Hudson yellow 1.0 Hiltamine arctic white SOL 1.5 100.0 FORMULA 2 Ingredients % by weight Amaco solv. E95 24.0 di octyl sebecate 55.0 Drapex 6.8 18.0 Hudson yellow 1.0 MDAC 2.0 100.0 FORMULA 3 Ingredients % by weight Aromatic solvent R 24.0 di octyl phthalate 50.0 Drapex 6.8 9.0 di ethyl phthalate 5.0 Monoplex S73 9.0 Hudson Yellow 1.0 Hiltamine arctic white SOL 2.0 100.0 FORMULA 4 Ingredients % by weight Panasol AN-2K 24.0 di octyl phthalate 55.0 Bakelite ERL-4289 18.0 Hudson yellow 1.0 Hiltamine arctic white SOL 2.0 100.0 To test for heat stability, nickle chrome test panels with cracks therein (obtainable from Eishin Kagaku Company, Inc.) are processed as follows: penetrant is applied, and after ten minutes the panels are immersed for 60 seconds in an emulsifier (Group V of Mil-I-25135C). The panels are then rinsed for 120 seconds in water, issuing from a tap at 20 psi.

The panels are then force air dried for 5 minutes at 130 F. Developer is applied (for example Fluro-chek DD-2) with 10 minutes dwell. The panels are then examined under ultraviolet light (for comparison purposes, two penetrants may be applied side by side on a panel). The panels are then placed in a forced air stream kept at 150 F, for 30 minutes (for example). They are then again viewed under black light. The two penetrants may then be compared as to fading properties. Typical cracks which can now be visibly seen using the above formulas, but which could not be seen before, have the following characteristics: width of crack .3-2 microns depth of crack about 50 microns It should be noted that heating the panels after application of the developer is not a normal process procedure and is for comparison purposes only.

Normally, the panel would be heated before the developer is applied. Comparisons can, of course, also be made this way.

Claims

1. A post emulsifiable penetrant composition for application and entry into flaws in solid surfaces, consisting essentially of a) a first solvent ingredient comprising a high boiling point aromatic hydrocarbon, b) a second solvent ingredient selected from the group that includes di-phthalates and diesters, c) epoxidized material selected from the group that consists of epoxidized esters, oils and resins, d) fluorescent dye, and e) fluorescent brightener.

2. The composition of claim 1 wherein the first solvent is selected from the group that includes: PANASOL AN-3, PANASOL AN2K, Amsco-Solv E 95, Hi sol 4-1, Chartersol 4-P, and Aromatic solvent R.

3. The composition of claim 1 wherein the first solvent consists of PANASOL AN-3.

4. The composition of any one of claims 1-3 wherein said second solvent consists of dioctyl phthalate.

5. The composition of any one of claims 1-3 wherein said second solvent is selected from the group that includes dioctyl phthalate, diethyl phthalate, dibutyl phthalate, diisodecyl phthalate, diisooctyl phthalate, di(n-octyl, N-decyl) phthalate.

6. The composition of any one of claims 1-5 wherein said epoxidized material is selected from the group that includes DRAPEX 6.8, DRAPEX 3.2, DRAPEX 4.4, FLEXOL plasticizer LOE, and MONO PLEX S-73, PARAPLEX G-62, and liquid epoxy resin.

7. The composition of any one of claims 1-5 wherein said epoxidized material consists of DRAPEX 6.8.

8. The composition ofanyoneofclaims 1-7 wherein said fluorescent dye consists of a naphthalimide.

9. The composition of claim 8 wherein said naphthalimide consists of Hudson yellow.

10. The composition of any one of claims 1-8 wherein said fluorescent brightener consists of an MDAC or other coumarin derivative such as Hiltamine Arctic White SOL.

11. A post emulsifiable penetrant composition substantially as herein described with reference to any one of the Formula Examples.

11. The composition of any one of claims 1-10 wherein the weight percentages of said a)---e) ingredients are adjusted to produce visible fluorescence, under black light, in a groove of the following dimensions: i) width about .1-2 microns ii) depth about 10-50 microns

12. The composition of any one of claims 1 -11 wherein the weight percentages of said a)---e) ingredients are: a) about 23.0 b) about 54.0 c) about 18.0 d) about 1.0 e) about 4.0

13. The composition of any one of claims 1-11 wherein the weight percentages of said a)---e) ingredients fall within the following weight percent ranges: a) 1-40 b) 20-80 c) 10-25 d) 0.1-3.0 e) 0.1-4.5

14. A post emulsifiable penetrant composition substantially as herein described with reference to any one of the Formula Examples.

New Claims or amendments of claims filed on 11/1/83 Superseded claims 1 to 14

1. A post emulsifiable penetrant composition for application and entry into flaws in solid surfaces, consisting essentially of a) 1-40 percent, by weight, of a first solvent ingredient comprising a high boiling point aromatic hydrocarbon having a boiling point within the range offrom 1770to3160C, b) 20-80 percent, by weight, of a second solvent ingredient selected from the group that consists of phthalates, c) 10-25 percent, by weight of epoxidized material selected from the group that consists of epoxidized soy-bean oils or oils, d) 0.1-3.0 percent, by weight of fluorescent dye, and e) 0.1-4.5 percent, by weight, of fluorescent brightener, f) said weight percentages adjusted to produce visible fluorescent under blacklight in a groove of the following dimensions, i) width from 0.1-2 microns ii) depth from 10-50 microns

2. The composition of claim 1 wherein the first solvent is selected from the group that includes: PANASOL AN-3, PANASOL AN-2K, Amsco Solv E 95, Hi sol 4-1, Chartersol 4-P, and Aromatic solvent R.

5. The composition ofanyoneofclaims 1-3 wherein said second solvent is selected from the group that includes dioctyl phthalate, diethyl phthalate, dibutyl phthalate, diisodecyl phthalate, diisooctyl phthalate, di(n-octyl, n-decyl) phthalate.

6. The composition of any one of claims 1-5 wherein said epoxidized material consists essentially of DRAPEX 6.8.

7. The composition of any one of claims 1-6 wherein said fluorescent dye consists of a naphthalimide.

8. The composition of claim 7 wherein said naphthalimide consists of Hudson yellow.

9. The composition of any one of claims 1-7 wherein said fluorescent brightener consists of an MDAC or other coumarin derivative such as Hiltamine Arctic White SOL.

10. The composition of any one of claims 1-9 wherein the weight percentages of said a)---e) ingredients are: a) 23.0 b) 54.0 c) 18.0 d) 1.0 e) 4.0