CN1330118A

CN1330118A - Allochroic paint with time indication function and its preparing process

Info

Publication number: CN1330118A
Application number: CN 00109194
Authority: CN
Inventors: 张翼; 李文铎; 周治东
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-06-15
Filing date: 2000-06-15
Publication date: 2002-01-09

Abstract

A chromotropic paint with time indication function is prepared from pH indicating agent as chromotropic agent, solid alkali as promoter, acrylic resin or emulsion as film forming substance, and organosilicon resin as coating agent. The thickness of coated layer can be used to control the colour-change time. It can be used for the package of food to indicate the quality guarantee period of food.

Description

Discolored with time display function coating and its preparation method

The present invention is a color with a time display function coating and its preparation method, which can over time at a certain temperature Produce a variety of changes irreversible color change, that is a time - between the color corresponding to the color coatings.

This coating can be used for commodities (especially food) packaging labels, printed as images or text to display its shelf life, Relative to the date of printing methods can better improve the appearance of the packaging sense and credibility.

The coating of the invention include discoloration agent, agent of change agents, film-forming material and coating agent.

Discoloration agent: It is a kind of molecular structure or composition changes when after the substance can produce color changes. Such as acid-base indicator, sensitive Indicator.

Promoting change agents: agents can induce discoloration discoloration of the material. Such as acid or alkali can induce acid-base indicator color, iron ions can iron test Agents discoloration, zinc ions can zincon discoloration.

Film-forming substance: Preparation of coating binders. Including (a) emulsion type: acrylic emulsion, white latex, vinyl acetate-acrylate emulsion: (2) Solvent: acrylic resin, alkyd resin, epoxy resin.

Coating agents: the color agent and / or agent of change agent to coat granular appearance. The use of different coating material, the thickness of the non-coated Same, the color change agent and promoting mutual penetration agent to control the speed. Thereby controlling the discoloration time. Cladding material selection principles: (1) does not adversely affect the coating material, with no chemical reaction; (2) no adverse reactions with the film material. (3) Have a certain porosity, that is coated with a permeable material.

The coating delay discoloration principle is: discoloration agent and agent of change agents constitute a reaction, once mixed color change will occur Technology, but this discoloration occurs in a short time period. Therefore, the present invention is characterized by the use of some of the instantaneous color change right, Their appearance will be separately coated particles, discoloration agent and agent of change agents must penetrate through the coating layer can migrate from contact with each other The discoloration reactions. So we can by changing the type and thickness of the coating layer to control the color change speed in order to meet the food Has a different shelf life requirements.

Coating agents include silicone resin, epoxy resin, polyurethane resin, etc., used in the present invention is a silicone resin coating agent.

Various discoloration agent and promoting behavior change agents discoloration in Table 1:

Table 1: discoloration agent and agent of change agent in the film-forming material in the color behavior

Discoloration agent	Promoting change agent	Membrane material	Results
Discoloration agent	Promoting change agent	Membrane material	Results	2,2 '- bipyridine	Ferrous ammonium sulfate	Acrylic	Yellow becomes pink.
Magnesium Reagents	NaOH	Acrylic	Dark brown discoloration deep brown.	2,2 '- bipyridine	Ferrous ammonium sulfate	Acrylic	Yellow becomes pink.
Magnesium Reagents	NaOH	Acrylic	Dark brown discoloration deep brown.	Methyl esculetin	NaOH	Acrylic	Naturals variable rhubarb (Seyan)
Cresol red	NaHCO ₃	Acrylic Emulsion	Marriage red to red.	Methyl esculetin	NaOH	Acrylic	Naturals variable rhubarb (Seyan)

Methyl red	Na ₂CO ₃	Acrylic Emulsion	Purple to yellow.
Methyl red	Na ₂CO ₃	Acrylic Emulsion	Purple to yellow.	Thymol blue	Na ₂CO ₃	Acrylic Emulsion	Dark purple pale blue
NaOH	Acrylic	Dark purple pale blue			Na ₂CO ₃	Acrylic Emulsion	Dark purple pale blue
NaOH	Acrylic	Dark purple pale blue	Bromine thymol blue		NaHCO ₃	Acrylic Emulsion	Golden pale blue
NaOH	Acrylic	Golden pale blue.			NaHCO ₃	Acrylic Emulsion	Golden pale blue

Note: at room temperature, to join the discoloration agent 0.2g and 4.0g resin uniform grind in a mortar, then add 0.4g of research to promote change agent, and then observe the Color effects.

The table of the color of the agent and agent of change agents were coated with a silicone resin, and the two respective groups formulated coating Points (a) and the component (2), then a certain mixing ratio, brushing on paper or iron sheet, found to produce different degrees of Delay discoloration function, as described embodiments.

Example one:

In with a reflux condenser, constant pressure funnel, a thermometer and a stirrer, 250ml four-neck flask, adding an organic coating agent Silicone resin (GD-01) 1.0 g, chloroform (CHCl₃) 60 g to 300 rpm / min speed Stir until completely dissolved Added after grinding into 300 mesh powder particulate accelerator NaOH8 g at 300 rpm at 50 ℃ / min stirring uniform rate Mixed condition, wetting 20min, then the constant speed of the funnel was added dropwise to hexane 5ml/min 70g coated 1.5 hours End. The solid was filtered, washed 2-3 times with n-hexane, 40 ℃ dried to constant weight to obtain 8.08g of solid powder particles, the Component (1).

The discoloration agent 300 mesh powder granular thymol blue (C₂₇H ₃₀O ₅S) 0.2 克 coated according to the method described above, and then , And 25 g of the acrylic resin in 250ml containers at 800 rpm / min speed stirring 20min, to obtain the component (2).

When using the component (1) 2 g of component (2) 25 g hand mixing in a vessel 5min, dubbed color paint, painted Brush the sheet of paper and tinplate sheet, the test piece at 4 ℃ refrigerator, color changes observed and recorded regularly every day. Table 2:

Table 2: The color coating (first embodiment) at 4 ℃ color change

Time	Color	Color code
Time	Color	Color code	Day 1	Navy	2748C
Day 2	Blue and gray	2767C	Day 1	Navy	2748C
Day 2	Blue and gray	2767C	Day 3	Deep dark green	447C
Day 4	Dark green	574C	Day 3	Deep dark green	447C
Day 4	Dark green	574C	Day 5	Olivine	573C
Day 6	Yellow green	581C	Day 5	Olivine	573C
Day 6	Yellow green	581C	7th day	Yellow green	456C

Day 8	Yellow	1245C
Day 8	Yellow	1245C	Day 9	Yellow	1245C
Day 10	Golden	124C	Day 9	Yellow	1245C
Day 10	Golden	124C	Day 12	Golden	124C

Note: The color code for Pantone (PANTONE) Company Color Formula Guide.

Example two:

In with a reflux condenser, constant pressure funnel, a thermometer and a stirrer, 250ml four-neck flask, adding an organic coating agent Silicone resin (GD-01) 1.0 g, chloroform (CHCl₃) 60 g to 300 rpm / min speed Stir until completely dissolved Added after grinding into 300 mesh powder particulate accelerator NaHCO₃10 grams of 300 rpm at 50 ℃ / min uniform rate Under stirred conditions, wetting 20min, then the constant speed of the funnel was added dropwise to hexane 5ml/min 70g coated for 1.5 O'clock. The solid was filtered, washed 2-3 times with n-hexane, 40 ℃ dried to constant weight to obtain 10.5 g of solid powder particles, Of component (1).

The discoloration agent 300 mesh powder granular bromine thymol blue 0.2 g coated according to the method described above, and then with 25 g C Acrylic resin in 250ml containers at 800 rpm / min speed stirring 20min, to obtain the component (2).

When using the component (1) 2 g of component (2) 25 g hand mixing in a vessel 5min, dubbed color paint, painted Brush the sheet of paper and tinplate sheet, the test piece at 4 ℃ refrigerator, color changes observed and recorded regularly every day. Table 3:

Table 3: The color coating (second embodiment) at 4 ℃ color change

Time	Color	Color code
Time	Color	Color code	Day 1	Navy	2748C
Day 2	Blue and gray	2767C	Day 1	Navy	2748C
Day 2	Blue and gray	2767C	Day 3	Deep dark green	447C
Day 4	Dark green	5743C	Day 3	Deep dark green	447C
Day 4	Dark green	5743C	Day 5	Dark green	574C
Day 6	Olivine	456C	Day 5	Dark green	574C
Day 6	Olivine	456C	7th day	Naturals	1255C
Day 8	Golden	124C	7th day	Naturals	1255C

Note: The color code for Pantone (PANTONE) Company Color Formula Guide.

Claims

1 having a time display function of color coating, characterized in that the color of this coating agent, agent of change agents, coating agents and a Film material formed.

2, according to claim 1, the invention is characterized in that color change agent agent agent and a reaction to form a color of the color used in the invention Agents such as acid-base indicator: thymol blue (thymol blue), bromine thymol blue, bromocresol green, etc.; promoting change agent Solid alkaline substances such as: NaOH, KOH, Na₂CO ₃、NaHCO ₃And so on.

3 according to Claim 1 and 2, the present invention is characterized by the use of a silicone resin coating material, the color change agent agent agent or a package Covered, in order to achieve the time delay and control discoloration purpose.

4 A process for preparing the coating color was the coating process, characterized in that the silicone coating agent is 0.5 to 20% of the chloroform solution 10 to 20 parts liquid, discoloration agent (or agent of change agent) 1 to 10 parts; precipitant 20 to 100 parts of n-hexane, coating temperature of 20 to 150 ℃, preferably 50 ~ 80 ℃; coating time 0.5 ~ 10h, preferably 1 ~ 2h.

5, according to claim 1, the film material used in the present invention are: acrylic resins and acrylic emulsions.